HEALTH AND DRUG ALERTS P RACTICE Asthma drug zafirlukast (Accolate): serious hepatic events Reason for posting: Zafirlukast the prophylaxis and chronic and the drug stopped if hepato- is an oral leukotriene receptor treatment of asthma in patients toxic effects develop. In most antagonist used in the treat- older than 12 years.2 Several cases, mild hepatic dysfunction ment of chronic asthma. Since drugs have been recognized to seems to reverse after discontinu- the drug was first marketed in interact with zafirlukast, includ- ation of the drug, but in some 1996, more than 100 cases of ing warfarin, erythromycin, cases the condition progresses to significant liver dysfunction ASA, theophylline and terfena- fulminant hepatitis or hepatic have been reported worldwide, dine. According to the product failure despite early detection of a including 14 of liver failure.1 In monograph, other adverse ef- problem and discontinuation of some cases, no symptoms or fects associated with the drug the medication. It is unclear signs of liver dysfunction were include hypereosinophilia, whether this adverse effect is reported before the severe he- hematologic abnormalities (e.g., shared with other members of patic injury occurred. Ten bruising, bleeding and agranu- the leukotriene receptor inhibitor cases, none fatal, have been re- locytosis), edema, arthralgias class, including montelukast. ported in Canada. The growing and myalgias. number of hepatic adverse Eric Wooltorton events recently prompted the What to do: Zafirlukast should CMAJ drug’s manufacturer, Astra not be prescribed to patients with Zeneca, to warn health care hepatic dysfunction. Patients re- References professionals about this rare but ceiving the drug should be 1. Important safety information regard- ing reports of serious hepatic events in potentially serious adverse warned of these rare but poten- patients receiving Accolate (zafirlukast) event. tially serious hepatic adverse ef- [Dear HealthCare Professional Let- fects and urged to immediately ter]. Mississauga (ON): AstraZeneca Canada Inc.; 2004 Apr 14. Available: The drug: Zafirlukast selectively report any symptoms of concern, www.hc-sc.gc.ca/hpfb-dgpsa/tpd-dpt competes for the leukotriene D4 including pain in the right upper /accolate_2_hpc_e.html (accessed 2004 Apr 30). and E4 receptors, both of which quadrant, nausea, vomiting, 2. Boulet LP, Becker A, Bérubé D, Bev- are implicated in the patho- anorexia, fatigue, lethargy, flu- eridge R, Ernst P; Canadian Asthma physiology of asthma. The drug like symptoms, pruritus or jaun- Consensus Group. Summary of rec- ommendations from the Canadian does not relieve acute broncho- dice. Serum transaminase levels Asthma Consensus Report 1999. DOI:10.1053/cmaj.1040720 spasm, but instead it is used for should be monitored periodically CMAJ 1999;161(11):S1-12. Canadian Adverse Reaction Newsletter Bulletin canadien des effets indésirables To receive the Newsletter and health product Advisories by email, join Health Canada’s Health_Prod_Info mailing list. Go to www.hc-sc.gc.ca/hpfb-dgpsa/tpd-dpt/subscribe_e.html. Inscrivez-vous à la liste Info_Prod_Santé de Santé Canada pour recevoir par courriel le Bulletin et les Avis au sujet des produits de santé. Rendez-vous à l’adresse www.hc-sc.gc.ca/hpfb-dgpsa/tpd-dpt/subscribe_f.html. Report adverse reactions toll free to Health Canada Signaler sans frais des effets indésirables à Santé Canada Tel./Tél. : 866 234-2345 • Fax/Téléc. : 866 678-6789 Email/Courriel: [email protected] 1668 JAMC • 25 MAI 2004; 170 (11) © 2004 Canadian Medical Association or its licensors.